Endocrine Abstracts

Background: Epidemiologocal data suggest an continuous increase in thyroid carcinoma diagnosis. Therefore, thyroidectomy rates are projected to increase world-wide in exponential scale. In Switzerland, the institutional number of thyroidectomies varies, however there is no data yet on the association between institutional thyroidectomy volume and clinical outcome.

Methods: Cross-sectional analysis of adult inpatients in Swiss hospitals using a nation-wide inpatient database covering the years 2011–2015. The study population consisted of adult (≥18 years) inpatients who underwent total thyroidectomy or hemithyroidectomy as the primary procedure. Hospitals were stratified into very low (<20 thyroidectomies per year), low (20–100 thyroidectomies per year), intermediate (101–200 thyroidectomies per year) and high (>200 thyroidectomies per year) thyroidectomy volume institutions. Multivariate regression models were used to determine complications, length of hospital stay (LOS), intensive care unit admission (ICU), 30-day readmission rates, and mortality in relation to hospital volume.

Results: A total of 17,410 patients were included whereof two-thirds (11,613; 66.7%) of thyroidectomies were performed at very low and low volume hospitals and one-third (5,797, 33.3%) at intermediate and high-volume hospitals, respectively. Operations of malignant thyroid diseases were more frequent among high-volume hospitals compared to low-volume hospitals (27.7% vs. 17.4%; P<0.001). Rates of hypocalcemia following thyroidectomy were lowest in high-volume hospitals (very low 6.7%, low 9.5%, intermediate 9.7%, and high 3.7%) with an overall adjusted odds ratio of 0.34 (95% CI, 0.29–0.42; P<0.001). Rates of recurrent laryngeal nerve paralysis were overall low at 2.1% (SD 14.5) for both total and hemithyroidectomies, just as mortality rates which did not show significant differences in relation to institutional number of thyreoidectomies (overall 8 deaths (0.05%). Length of stay revealed a bell-shaped curve and was lowest among high-volume hospitals when compared to other hospital volume with a mean difference of 0.61 days (95% CI; (−0.72)–(−0.50); P<0.001).

Conclusions: Despite higher rates of malignant thyroid diseases, high-volume hospitals had less or comparable complications and shorter length of stay following thyroidectomy when compared to hospitals with low thyroidectomy volume. Mortality rate was low and independent of institutional thyroidectomy volume.